Certain types of garden worms are common across the globe. These include night crawlers, red wigglers, and tiger worms. Other worms are common for specific regions, but are non-existent in other areas. For example, the Malaysian blue worms are quite easy to find in tropical regions, but will not be found in arid areas of the world. Each of the types of gardening worms work to break down the soil, making it rich for growing a wide range of garden plants.
Night crawlers are large garden worms that are usually reddish in color, with the tail being lighter than the front end. They are fully mature in about one year and as they become older, they turn gray in color. They live about six years, making them one of the longer-living types of garden worms. Although most night crawlers are about 5 inches (12.7 cm) long, they are capable of reaching 10 inches (about 25.4 cm) in length.
Night crawlers are considered valuable garden worms. They create tunnels deep into the soil and transport rich nutrients from the top of the soil down to about 6 feet (1.8 meters) under the surface. Not only will the tunnels formed by these worms create healthier soil and, therefore, plants, but the tunnels also help the soil drain more efficiently, preventing rot and other diseases from affecting garden plants.
Red worms, also called dung worms, red wrigglers, or red marsh worms, are also common garden worms. They are reddish-brown in color, and may have pale yellow-tinged coloring on their undersides. These worms mature in about six months, but live about two years. As adults, they can grow as long as 4 inches (about 10.2 cm) long, but many only reach lengths of a single inch (about 2.5 cm).
Red worms are considered helpful garden worms as well. They produce waste that helps enrich the soil composition. They also break-down organic material, such as compost, found in many gardens. As a result, they work to make the soil fertile and help plants grow well, even if the natural soil conditions are shoddy.
Tiger worms, also referred to as manure worms, are much tinier than other garden worms. They are usually deep reddish-purple in color and have yellow bands that create stripes down the lengths of their bodies. They mature quickly, taking only six to eight weeks to mature, and they can live approximately four years. In addition, they rapidly reproduce, forming several hundred cocoons each year. These worms are typically about 1 inch (2.5 cm) long, though they have been known to grow much longer, if the conditions are right.
Although the night crawlers, red worms, and tiger worms are found in many areas around the globe, there are certain garden worms that are common in select areas. For example, in tropical areas, such as Thailand and China, Malaysian blue worms are common. These worms have a bluish-purple color and a light yellow underside. They also work to break down the soil, making them popular for gardeners interested in composting.